From Logical Positivism to 'Metaphysical Rationalism': Isaiah Berlin on the 'Fallacy of Reduction'

Isaiah Berlin's (1909-97) standing in twentieth-century intellectual history rests primarily upon his post-Second World War writings in political theory and the history of ideas. Berlin's investigations into the antagonistic traditions of Enlightenment and Counter-Enlightenment thought, and his advocacy of liberal responses to the conflicts between values, which, he believed, were an unavoidable feature of the human condition, have been the subject of extensive discussion. Less has been written, however, about Berlin's formative experiences of analytic philosophy during the 1930s and late 1940s. It is often assumed that Berlin 'abandoned' philosophy after the war in favour of the history of ideas. As such, there is a tendency in much of the existing literature to underestimate the influence of Berlin's early analytical work on his later historical and political writings. Indeed, Berlin's work is regularly thought to be marked by a fracture at which point the study of philosophy is relinquished for that of history and political theory. The present article will aim to challenge this reading of Berlin's work. The article will advance two main claims. Firstly, it will be argued that not only is Berlin's early work in analytic philosophy of interest to those concerned with the development of his thought as a whole but also that it is highly edifying for any understanding of the nature of the outlook contained in his later writings. Secondly, the article will maintain that there exists a degree of continuity in Berlin's thought that connects his earlier and later work in a manner reflecting a greater level of coherence than is generally assumed. The main theme of continuity emphasized in the article is represented by Berlin's critique of what he terms the 'fallacy of reduction'.